That is where my problems start: I cant find my Windows XP installation CD and the licence key.
Your last question first: I have scanned the Windows Vista installation with MalwareBytes in Save modus: No problems found. I have scanned with Ad-Aware: No serious problems found (only some cookies). Have scanned with Avast: no problems found. I see no suspicious activity on my modem/router, I have checked all processes in Taskmanager, by looking them up on the internet: also no problems.
If above is not good enough I do not know what I can do more. I'm aware that there is always a posiblity that a very clever Virus is capable of hiding from virus and/or Malware scanners. But I also think that it is impossible to have your PC perfectly protected (exept for never use it or switch it on
The first part of your reply: Yep, Both Vista and XP were on volumes on the same disk. I have tried to remove XP, which succeeded mostly, but I have some folders, parts of the "my documents" chain, that seem imposible to delete. (but are eating up 8GB of space)
If not nececary, I do not want to reinstall XP, Vista works Fine for me. I also can not reinstall vista because I have lost the license key and the instalation media (were in the same pouch as my XP installationkit)
So if there is a way to free up the Boot volume, other than formatting, that would be nice, because it saves me from Buying a new OS and all programs I have installed.
The other option is leave it as it is, it works under Vista OS. But I consider this as a waste of Valuable disk space